Bug 1229343

Description of problem:
When going through the user guide to install RDO Manager on Centos7, instack-virt-setup fails when trying to connect to the hypervisor:

brbm
+ virsh net-list --persistent
+ grep 'brbm '
error: failed to connect to the hypervisor
error: no valid connection
error: no connection driver available for qemu:///system
error: Failed to reconnect to the hypervisor

libvirtd shows:
Jun 05 13:54:38 foreman-server.ci.com libvirtd[26339]: failed to load module /usr/lib64/libvirt/connection-driver/libvirt_driver_storage.so /usr/lib64/libvirt/connection-driver/l...e reference
Jun 05 13:54:38 foreman-server.ci.com libvirtd[26339]: failed to load module /usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so /usr/lib64/libvirt/connection-driver/libv...eFileCreate

Updating device-mapper packages fixes the problem:
[root@foreman-server ~]# yum update device-mapper
Loaded plugins: fastestmirror, langpacks, priorities
Loading mirror speeds from cached hostfile
 * base: mirrors.usc.edu
 * epel: mirrors.cat.pdx.edu
 * extras: mirrors.cat.pdx.edu
 * updates: mirrors.sonic.net
199 packages excluded due to repository priority protections
Resolving Dependencies
--> Running transaction check
---> Package device-mapper.x86_64 7:1.02.84-14.el7 will be updated
--> Processing Dependency: device-mapper = 7:1.02.84-14.el7 for package: 7:device-mapper-event-1.02.84-14.el7.x86_64
--> Processing Dependency: device-mapper = 7:1.02.84-14.el7 for package: 7:device-mapper-libs-1.02.84-14.el7.x86_64
---> Package device-mapper.x86_64 7:1.02.93-3.el7 will be an update
--> Running transaction check
---> Package device-mapper-event.x86_64 7:1.02.84-14.el7 will be updated
---> Package device-mapper-event.x86_64 7:1.02.93-3.el7 will be an update
--> Processing Dependency: device-mapper-event-libs = 7:1.02.93-3.el7 for package: 7:device-mapper-event-1.02.93-3.el7.x86_64
---> Package device-mapper-libs.x86_64 7:1.02.84-14.el7 will be updated
---> Package device-mapper-libs.x86_64 7:1.02.93-3.el7 will be an update
--> Running transaction check
---> Package device-mapper-event-libs.x86_64 7:1.02.84-14.el7 will be updated
---> Package device-mapper-event-libs.x86_64 7:1.02.93-3.el7 will be an update

Restarting libvirtd shows no errors, and then instack-virt-setup re-runs succesfully.  This package should be added into the script.

My CentOS version: CentOS Linux release 7.0.1406 (Core)